What had to be added to the U. S. Constitution for the Anti-Federalists to ratify it and why did this need to be added?

The Bill of Rights

Explanation:

The Anti-Federalists(Anti-Fed) were composed of mainly laborers, land owners, shopkeepers and so on. The Anti-Fed were afraid that the power and authority being invested in the national government would take away from that of the state government, they preferred the state government having the power because they felt that it gave their voice more power when it came to elections or public favor etc. The Anti-Fed pushed back on the idea of a strong national government and the ratification of the constitution until they were promised that measures would be taken to protect their individual liberties which birthed the bill of rights.

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